• Journal of Surface Science and Engineering
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• v.30 no.3
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• pp.191-201
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• 1997

Non-passivated electrolytic tinplates withour conventinal chemical treatment self-oxidize in ambient atmosphere to from yellow stain on the outermost surface during the long-term storage. The degree of yellowness of the stain increased linerly with the oxide thickness due to the interfeefence color of the $SnO_2$ Even though the thickness of the oxide layer was very thin, less than 100$\AA$ , it exerts an undesirable influence on the can-making processes, particularly the stripping behavior after ironing. Investigations were carried out on the morphologies of the coating layer, the changes in oxide thickness during successive can-making processes and the averge friction coefficients with the different oxide thinkness. These oxide layers were broken up and distributed within the bulk tin coating during the ironing process. This redistribution of the oxide layer prvented smooth pressing-aside of the tin coating layer, resulting in an increase in the ironing friction coefficient. As the friction was increased, the residual stress along the can wall thinkness(i.e., the hoop stress) was also increased. Due to both the oxibe layer accumulation, which increased the friction coefficient, and the hoop stress, can stripping efficiency without roll-back is reduced.

• Journal of Korean Institute of Industrial Engineers
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• v.16 no.1
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• pp.67-81
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• 1990

Effectiveness of physical exercise in reducing work-related musculoskeletal stress was investigated. This was compared to the stress alleviation accomplished by using ergonomically designed work station. Tasks chosen for the study were data entry and file maintenance on the video display terminal (VDT). Three different measures, namely root-mean-square (RMS) values of electromyogram (EMG), subjective rating and task performance were used for the evaluation. Electromyograms were recorded from the neck, the left and right trapezius muscles in the shoulder region, and L2/L3 region of the back. Subjects rated discomfort levels for the same parts of their body. Task performance was measured by recording typing speed and errors. Each of the five subjects was tested for two days (8 hours/day) in two different work stations. These were the ergonomically designed adjustable work station and the fixed work station of traditional design with no adjustable features. Assigned physical exercises were performed for four minutes, every two hours during the breaks, by the subjects while working in the fixed work station. It was concluded that the physical exercise could be helpful in reducing musculoskeletal stress as effectively as the ergonomic design of the VDT work station.

• CELLMED
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• v.9 no.3
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• pp.4.1-4.8
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• 2019

Now researchers have focused attention on exploring the mechanism of acute responses of heat stress given in heat therapy that ultimately promotes the long term health benefits. Heat therapy is not a new idea rather it was practiced since thousands years back in the form of hot bath, sauna bath, steam room. Similarly in Ayurveda there is very comprehensive description of heat therapy in the form of Svedan karma (Sudation therapy). Svedan is a process to induce sweating artificially in a patient who had already undergone Snehan. Svedan is applied for purification of body, as well as in management of various disorders originated due to vitiation of Vata, Kapha Dosha, Meda Dhatu and musculoskeletal disorders. It produces various beneficial effects by augmenting the Agni like clears the channels, liquefies the deposited Dosha, regulates Vata Dosha, helps in removal and pacification of Dosha, augments metabolism (Agni Deepan), increases appetite, flexibility in body parts, softness and shining of skin, removes coldness, stiffness, drowsiness, improves joint motility. However, Svedana karma is vastly used by Ayurveda Physicians in treatment of various disorders but the mechanisms of beneficial effects produced by Svedan Karma are yet not completely explored on scientific basis. In this article, we will discuss and try to establish a possible mechanism of action of Svedana karma in relation to heat stress, mitochondrial adaptation, heat shock protein (HSP) and glucocorticoids as these are secreted under stressful conditions.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.5
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• pp.389-399
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• 2016

Efficiency for estimation of subsea tunnel safety can be increased through reflecting back analysis algorithm to displacement measurements besides other measurement information such as stress, water pressure and ground stiffness degradation. In this study, the finite difference code FLAC3D built-in FISH language is used. In addition, the stability of the tunnel lining will be evaluated from the development of displacement-based algorithm and its expanded algorithm with conformity of several parameters such as stress measurements, water pressure measurements, tunnel lining degradation measurements and ground stiffness degradation measurements. By using additional measurement information to assess the stability of subsea tunnel, it was confirmed that the error rate is reduced to the tunnel back analysis.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.3
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• pp.250-260
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• 2005

This study was designed to find the symptom prevalence rates of musculoskeletal disorders and the risk factors of musculoskeletal disorders among selected hair dressers. Methods; The survey were conducted from July 1 to 30, 2004 for 459 hair dressers working in Seoul and Gwangju using self-administration questionnaire. The risk factors on musculoskeletal disorders have analysed by multiple linear regression analysis. The results of this study are summarized as follows: The experience rate of musculoskeletal disorders symptom in the last one year was 56.4%. The experience rates of each body parts were 36.4% on the shoulders, 30.5% on the legs and the feet, 28.5% on the low back, 27.0% on the hand and the fingers, 23.3% on the neck and 17.0% on the arms and the elbows. The prevalence rate of musculoskeletal disorders symptom in the last one week was 40.5%, those of each body parts were 24.0% on the legs and the feet, 21.4% on the shoulders, 20.7% on the low back, 15.7% on the hand and the wrists, 15.0% on the neck, 9.4% on the arms. The risk factors on musculoskeletal disorders were working posture(${\beta}=0.32$), perceived stress(${\beta}=0.19$), working period(${\beta}=0.16$), standing working over 10 hour(${\beta}=0.16$), hard working(${\beta}=0.11$). The adjusted determinant coefficient($R^2$) of this regression model was 0.267. Based on the results, in order to prevent musculoskeletal disorders of hair dressers, working posture shall be improved and leisure opportunities to relieve stress, and health management program shall be provided.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.9
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• pp.1627-1634
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• 2017

In this work, a junctionless transistor with different film thickness of amorphous InGaZnO has been fabricated and it's instability has been analyzed with different film thickness under positive and negative gate stress as well as light illumination. It was found that the threshold voltage shift and the variation of drain current have been increased with decrease of film thickness under the condition of gate stress and light illumination. The reasons for the observed results have been explained by stretched-exponential model and device simulation. Due to the reduced carrier trapping time with decrease of film thickness, electrons and holes can be activated easily. Due to the increase of vertical channel electric field reaching the back interface with decrease of film thickness, more electrons and holes can be accumulated in back interface. When one decides the film thickness for the fabrication of junctionless transistor, the more significant device instability with decrease of film thickness should be consdered.

• Geotechnical Engineering
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• v.2 no.3
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• pp.51-66
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• 1986

The design of fabric reinforced retaining wall structure was discussed in this article. It was confirmed that the reinforced retaining earth wall which was designed by new theoretical formulae developed this time was stable structurally and economically. The plastic fabric filter which was placed in layers behind the facing element reduced the lateral earth pressure on the wall elements in comparison with a conventional retaining earth walls. The reinforcing characteristics of earth wall was governed by the spacing of fabric layers, effective length of fabrics, particle distribution and compaction, and thus it is essential that, in the construction field, the reinforcing strips should be selected in order to develop the maximum friction forces bet.eon soil and fabric filters. The maximum tensile stress developed from the reinforcing strips was appeared at a little far distance from the back of skin element and it was not well agreed with the Rankine's theory but distributed well as a symmetrical shape against the point of the maximum tensile stress. The total length of the different layers should be sufficient so that the tension in the fabric strip could be transferred to the backfill material. Also the total stability of reinforced earth wall should be checked with respect to a failure surface which extended blond the different lathers.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.267-278
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• 2003

Artificial neural networks are efficient computing techniques that are widely used to solve complex problems in many fields. In this study, in order to predict tunnel-induced ground movements, Tunnel Behavior Prediction System (TBPS) was developed by using these artificial neural networks model, based on a Held instrumentation database (i.e. crown settlement, convergence, axial force of rock bolt, compressive and shear stress of shotcrete, stress of concrete lining etc.) obtained from 193 location data of 31 different tunnel sites where works are completed. The study and test of the network were performed by Back Propagation Algorithm which is known as a systematic technique for studying the multi-layer artificial neural network. The tunnel behaviors predicted by TBPS were compared with monitored data in the tunnel sites and numerical analysis results. This study showed that the values obtained from TBPS were within allowable limits. It is concluded that this system can effectively estimate the tunnel ground movements and can also be used f3r tunneling feasibility study, and basic and detailed design and construction of tunnel.

• The Journal of Engineering Geology
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• v.18 no.2
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• pp.177-183
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• 2008

In the study, we carried out a 3-D analysis to assess the influence of groundwater level changes on the slope stability, conducting a series of back-numerical analysis to delineate the critical line of the shear strength of the failure surface of a landslide, and a laboratory test to determine the geo-mechanical properties of soil samples. The analysis result shows that the shear strength determined by the laboratory test was distributed below the critical line of shear strength estimated by back-analysis. Differences between driving and resisting force were also analyzed in groundwater conditions of dry and saturation. It appeared that the stress gets greater towards the slope center of the landslide, and the debris mass moves downwards. According to the analysis, the factor of safety becomes 1 with the rise of foundwater level up to -0.85 m from the slope surface, while the slope tends to stay stable during dry seasons.

• Journal of Oriental Neuropsychiatry
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• v.13 no.1
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• pp.127-132
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• 2002

This case show that emotional stress and wekness of gastrointestinal function occur a chronic hiccup and eructation(during 3 months), oriental medical therapy can cure completely this symptom. Seven emotional stress(anger, delight, sadness, thinking, worry, fear, horror) occur various pathologic changes. Hiccup is caused by CNS, psychologic, thoracic, abdominal factor etc. In oriental medicine, GI trouble regarded as a very importent factor that occur hiccup and eructation. Besides, emotional stress is a very important factor as well. This patient have an introvert personality ordinary times. One day, she had a miscarriage by hers husband's assault. After that time, she suffered from very serious GI trouble(dyspepsia, epigastric pain, anorexia). And then hiccup, eructation, weight loss(10kg/3months) is occured. This patient diagnosed only gastritis. This symptom did not stop during 3 months, regardless of western medical therapy(some western drugs medication, fluid supply etc). After oriental medical therapy(herb medicine;Yukunjatang, acupuncture;CV12, CV6, S36, CV17, H7, SP6, P6, moxibustion;VI2, CV6, S36, negative therapy;back area and traditional oriental medical psychotherapy;ventilation, support, desensitization and family interview) put in operation during 15 days, patient completely recover from hiccup, eructation and anxiety disorders.